The Many Uses for Rivets in CNC Machining(cnc machining prototype Flora)
- source:MAJA CNC Machining
Rivets come in a wide variety of styles, sizes and materials to accommodate different CNC machining needs. Some of the most common uses for rivets in CNC include:
Aircraft and Aerospace Applications
The aerospace industry relies heavily on rivets to assemble lightweight, high-strength structures. Aircraft skins are typically joined with flush head rivets, while other rivet types are used for structural joints. CNC machining is used to drill precision rivet holes and dimples into the aircraft skins and frame components. The holes are then riveted together by automated riveting machines or manually by technicians. Aircraft grade rivets are made of lightweight, corrosion resistant alloys like aluminum and titanium.
Sheet metal fabricators use rivets extensively to join thin gauge metals in products like enclosures, cabinets, trailers, ducting, and more. The most common rivets for sheet metal fabrication are blind rivets, which can be installed from one side without access to the back. CNC punch presses are programmed to punch or drill the rivet holes in sheet metal components. Operators then use manual, pneumatic, or automatic rivet installation tools to join the materials. Blind rivets come with different head styles to suit various fabrication requirements.
Rivets are ubiquitous in automotive manufacturing for assembling body panels, frames, interior parts, and under-hood components. Robotic CNC machining cells drill precision rivet holes into panels and parts that technicians later join together along the assembly line. Rivet types range from solid aluminum for panels to steel and acrylic for interiors. Robotic riveting systems install the fasteners in seconds to accelerate production speeds. Automotive grade rivets have high shear and tensile strength to withstand vibration and impact forces.
The manufacture of home and commercial appliances like refrigerators, washers, dryers, and HVAC equipment relies on rivets to assemble steel, aluminum, and stainless steel panels. CNC machining centers drill rows of rivet holes around the edges of the panels in specific patterns. The panels are then aligned and riveted together by workers on the assembly line or by automated riveting machines. Appliance rivets come in stainless steel, aluminum alloys, and coated steel to withstand humidity, condensation, and temperature swings.
Electronics Enclosure Manufacturing
Rivets provide reliable, vibration-resistant fastening for sheet metal electronics enclosures, racks, and small housings. CNC turret punch presses are ideal for punching small, dense rivet patterns into enclosure panels for components like servers, network switches, and industrial control cabinets. Rivet holes can also be drilled using CNC machining centers. Assemblers then use manual, electric, or pneumatic rivet guns to install the hardware on the production floor. Steel, aluminum, and stainless steel rivets with zinc plating provide durability.
Although plastics are commonly joined with adhesives or welding, plastic rivets are used for applications requiring mechanical fastening. Plastics like polycarbonate, PVC, ABS, nylon, and acrylic can be joined using plastic rivets. CNC routers machine rivet holes for plastic fabrication, typically in larger diameters than metal riveting. Installation tools provide controlled heat that temporarily softens the rivet so that it can expand within the hole as it hardens. Plastic rivets create durable, permanent joints while allowing for disassembly when needed.
Wood Product Manufacturing
The furniture, cabinetry, and construction industries take advantage of rivet’s holding power to assemble wooden frames and structures. CNC routers efficiently drill rows of rivet holes along wooden joints. Operators then use manual or pneumatic tools to drive the rivets into the holes and cinch the two sides together. The rivets firmly hold the joint together while allowing some flexibility and shock absorption. Common wood rivets have fluted shanks to grab onto the wood while aluminum and steel rivet heads provide clamping force.
Riveting for Heavy Machinery
Heavy machinery like bulldozers, cranes, graders, and forklifts use oversized rivets to assemble massive structural components and frames. Extra thick steel plates require large diameter rivet holes often measuring 1” across or greater. CNC drilling machines bored these oversized holes prior to hot riveting. The rivets are heated and applied with heavy hydraulic presses that upset the tail, spreading it into a second wide head. The result is an incredibly strong joint able to withstand extreme loads and vibration.
Maximum Strength Structural Connections
When an application calls for maximum strength in a thin profile, rivets outperform welds and bolts. Aircraft carriers, bridges, railcars, transmission towers, and building frames all utilize rows of specialty structural rivets. CNC machining drills the holes across beams and joining plates before workers muscle the heavy rivets into place. The rivets are often hydraulically pressed to flare out the tail into a wide shop head that distributes force across a greater area.
Low Cost, Easy Maintenance
Compared to welding, bolting, or bonding, riveting offers a cost-effective means for assembling products and materials. The rivets themselves are relatively inexpensive hardware. Minimal equipment is required for installation beyond hand tools for small scale jobs. CNC hole drilling improves efficiency for high volume production. Riveted assemblies can be easily disassembled for maintenance and repairs by simply drilling out the rivets. The holes can be re-riveted with oversized replacement hardware if needed. These advantages make rivets the top choice for many manufacturers.
Reliable Joining of Dissimilar Materials
One of the unique advantages of rivets is the ability to join completely different metals and materials. Aluminum sheets can be riveted to steel brackets. Plastic casings can be fastened to sheet metal backings. Fiberglass components can be attached to metal structures. The clinching force of the rivet shafts and heads creates a reliable bonding force even when the materials have very different properties. CNC machining allows drilling precise holes despite varying hardness and densities.
Water and Pressure-Tight Seal
For applications requiring a water or pressure-tight seal, specialty fluid sealing rivets are available. Common types include blind seal rivets and drive seal rivets. Installation tools upset the rivet tails to flare outward, creating tight clamping force between the joined materials. Sealant rings can be integrated into the rivet design to enhance the fluid barrier. This allows riveted assemblies to be used in liquid storage tanks, chemical pipelines, hydraulic cylinders, and radiators. CNC machining ensures rivet hole alignment is precise enough to prevent leakage.
Permanent, One-Way Installation
In machinery and public applications where vandalism and tampering are concerns, permanent rivets provide one-way fastening. The act of upsetting and spreading the bucktail to form the second retaining head essentially locks the rivet in place forever. Attempting to disassemble a riveted assembly by drilling, cutting, or prying is difficult and damages the surrounding materials. Pop rivets in particular offer permanent one-way installation. Anti-tampering rivets require specialized CNC machining to drill the holes before assembly.
Corrosion and Chemical Resistance
For highly corrosive environments and challenging chemical exposures, special rivets are manufactured from materials like stainless steels, nickel alloys, and titanium. These corrosion resistant rivets maintain their clamping force and structural integrity when subjected to deicing fluids, salt spray, caustic cleaning agents, and acidic compounds. They are indispensable for equipment like oil rigs, seafaring vessels, pulp and paper plants, and wastewater treatment facilities. CNC machines provide rapid drilling of large rivet counts seen in these applications.
High Strength-to-Weight Ratio
Aircraft and aerospace manufacturers in particular take advantage of lightweight rivet alloys. Light metal alloys like aluminum, magnesium, and titanium provide rivet fastening with very high shear, tensile, and clamp loads relative to their low mass. This maximizes overall strength and performance of aircraft structures while minimizing weight for fuel efficiency. CNC laser and drilling machines are programmed to provide the holes and dimples for consistent high-quality rivet installation.
In summary, manufacturers across nearly every industry have made rivets integral components of their design and production processes. The versatility, strength, and durability of riveted joints has stood the test of time in all types of materials and applications. Advancements in rivet technology and CNC machining continue to expand possibilities for rivets in the future. Riveting remains among the most reliable and cost-effective methods of fastening and assembly. CNC Milling CNC Machining